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b=P9ikKe5M0p256JAWOmy5NpxEFMkd1pZJL5H1ErHaarxIVJt89Rx0Z7mrmEOcaP9bj OP0r9+Bq0mAi5xwOgvsk5wy05AHM0WC1nypEPbID7g0sA05crXE/HQ9vlK7XDdQMEZ nd0FhGT+RyLVFSLWdgoyRDFAYUgvnAo8n/uKLaQeY/xJYsV65hPL4y/AdCrV3Um6jF Q2gZznSezWmB6iQv9Ig1af65X6giq/al/H788jIiLeAsh2jvtTLt8D9738g9Ci75xQ n16q4pY8ss8GHXoozBP3AzV7JAlNULy4Emt0rLmlrUxBGssS8TTyDEptRGMYTr9v1b mrDIOXVgEjj4Q== Message-ID: <141d58e1-5663-482b-ab61-956f3b08081b@kernel.org> Date: Wed, 23 Sep 2026 19:19:57 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] mm/page_alloc: let the bulk and folio allocators carry alloc_flags Content-Language: en-US To: Gregory Price Cc: Lance Yang , linux-mm@kvack.org, linux-kernel@vger.kernel.org, kernel-team@meta.com, akpm@linux-foundation.org, surenb@google.com, mhocko@suse.com, brendan.jackman@linux.dev, hannes@cmpxchg.org, ziy@nvidia.com, david@kernel.org, ljs@kernel.org, liam@infradead.org, rppt@kernel.org, baolin.wang@linux.alibaba.com, nico.pache@linux.dev, ryan.roberts@arm.com, dev.jain@arm.com, baohua@kernel.org, usama.arif@linux.dev, kas@kernel.org, matthew.brost@intel.com, joshua.hahnjy@gmail.com, rakie.kim@sk.com, byungchul@sk.com, ying.huang@linux.alibaba.com, apopple@nvidia.com References: <20260914155115.439742-1-gourry@gourry.net> <20260922130558.48402-1-lance.yang@linux.dev> <80206444-d0c3-4dab-a5e3-a2909e58ea33@kernel.org> From: "Vlastimil Babka (SUSE)" Autocrypt: addr=vbabka@kernel.org; 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charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspamd-Server: rspam12 X-Rspamd-Queue-Id: DA04540004 X-Stat-Signature: yghck1ccciift8drry7k89czajdjh3fc X-Rspam-User: X-HE-Tag: 1790184005-964537 X-HE-Meta: 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 4CtzcIRs WHT5i2F7Ucj+FM8o8vurQnrrtBx4cRZibyJUcUMuAHzQbjwRURwoEh4FKHyO/+jqc+I4baxZ2W3eFLwyJ28GoNJZEPEFW3BIAfrQK8dFG+oHprKMfQGM9OFGXtyYlQXxeKfoUyWYh85MBf3cRL46FYdDyqayt5cpHJJEW0jJ+sDWGf/QZyqOz+SZ8f/4488+ImKOLQ/ZePQil1FFaR/szQ0W17caECp83YbAJUk8ybmkopfj73Z9oOBeMVJqkyoP5yhhIbD2gMoeGFRzg44XYyXWRJLqf2+h6Vvym+m9LGe6JG7D6I/NIu65bOWbgcEnjj4xj6+H8aF4fY5JUBBJa2LJTKsI8da2I0DIOC0ybXviWVB5g0r+OIv51htIAu4UEJQrk Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 9/23/26 17:24, Gregory Price wrote: > On Wed, Sep 23, 2026 at 08:32:29AM +0200, Vlastimil Babka (SUSE) wrote: >> On 9/23/26 03:59, Gregory Price wrote: >> > On Tue, Sep 22, 2026 at 09:05:58PM +0800, Lance Yang wrote: >> > >> > There is some concern around NOLOCK here yes, in fact sashiko picked >> > this issue up and I've been poking at it. >> >> It's possible to document it as unsupported, add a VM_WARN_ON_ONCE etc. >> It's not necessary for bulk alloc to support ALLOC_NOLOCK just because it >> takes flags. e.g. kmalloc_nolock() supports a subset of gfp flags as well. >> > > It seemed simpler to just support it than to create more future > footguns. I can RFC my current rework if you like, i attempted > to deduplicate the logic via a prepare_alloc_flags() called from > both the bulk and non-bulk contexts. Ok if it's simple enough, lets see :) Thanks > But if we prefer the WARNs over adding the new semantics to the bulk > allocator, that also doesn't seem unreasonable. > > ~Gregory